Liquid dispensing apparatus

ABSTRACT

A draft beer circuit for a series of rapidly intermittent pours, in which a flow pressure control valve is introduced between the beer keg and the spigot, adjacent the spigot, to effectively isolate the downstream portion of the beer circuit below the pressure control valve from the upstream portion, except during conditions of flow. The pressure of the fluid at the spigot is thereby maintained at flow pressure rather than spigot pressure, so that all timed pours are of constant volume.

ilnite States atent 1 ()lson 1*May 28, I974 4] LIQUID DISPENSINGAPPARATUS 3,408,036 l0/l968 Smith et al 222/70 x 3,464,591 9/1969 Nicola[76] Invent Verne 1924'29th 3,467,279 9/1969 Upton etal 222/70 x S.W.,Calgary, Alberta, Canada Notice: The portion of the term of this PrimaryExaminerLloyd L. King patent subsequent to May 28, 1990, has beendisclaimed. 57 ABSTRACT [22] Filed: Aug. 8, 1969 A draft beer circuitfor a series of rapidly intermittent pours, in which a flow pressurecontrol valve is intro- [21] Appl' duced between the beer keg and thespigot, adjacent the spigot, to effectively isolate the downstream por-[52] US. Cl. 222/70 on f he be r circ i below the pressure control [51]Int. Cl B670 5/08, G04c 23/38 valve from h up p except ng d [58] Fieldof Search 222/70, 179, 138 i n of flow. The pressure of the fluid at thespigot is thereby maintained at flow pressure rather than spigot [56]References Cited pressure, so that all timed pours are of constant vol-UNITED STATES PATENTS 3,248,009 4/1966 Sutton et al. 222/70 X 4 Claims,2 Drawing Figures l'lOV. AC

- AIR PATENTEDNAY 28 1974 LIQUID DISPENSING APPARATUS The presentinvention relates to improvements in mechanism for dispensing avolumetrically predetermined amount of liquid, and particularly relatesto a mechanism for dispensing a required volume of a liquid which tendsto foam at or near normal atmospheric pressure.

In the vending of draft beer from brewers kegs or barrels, it has beencustomary to tap the keg, under pressure, through a flow line into ahand-operated spigot or bar valve, operated by a tap-man fillingtherefrom a glass in accordance with a fill-line markedcircumferentially near the lip of the glass. Such an operation isnecessarily inaccurate and slow, particularly when the tap-man isoperating during periods of high activity when demand may run as high asl20 glasses of approximately 8-10 fluid ounces per minute.

Various systems have heretofore been proposed for the automation of theglass-filling operation, to provide a successively intermittent deliveryat the spigot of predetermined volumes of liquid, thereby permitting thetap-man to fill rapidly a succession of glasses. Such a system isnormally actuated by a manually operated switch controlling anelectrical timer which actuates a solenoid operatively connected to thespigot; successive pours are made until the switch is operated to theoff position,

The solenoid-operated spigot valve, actuated into the on position by themanual switch contact, successively opens and closes in response topulses from an electronic timing means, usually of the resistorcapacitortype of circuit. In this type of time-pulse circuit, an electricalcharge builds up in one or more capacitors which, in accordance with thecharacteristics of the circuit, discharges after reaching a determinablelevel, causing a current flow which is amplified to operate the spigotsolenoid to the open position. A succeeding pulse will operate thespigot solenoid to the close position, and a rest interval will follow,during which the tap-man will remove the filled glass from the spigot,and substitute an empty glass, for successive filling. Because of thefoaming characteristic of draft beer, it must be maintained underpressure throughout the circuit, in order to maintain the dissolvedgases in solution.

A constant pressure will normally exist throughout the system while itis in static equilibrium, which pressure in the normal draft beercircuit, is approximately 40 p.s.i. gauge. However, after the spigotvalve has remained open for a period of several seconds, the flowpressure at the spigot p, will reduce by the amount of the friction headthroughout the system, and in subsequent intermittent pours, the fluidpressure p, at the spigot during discharge will be substantially equalto the pressure on the keg p minus the friction loss. In an exampleregarded as typical, a friction head of 12 p.s.i. was developed underflow conditions between keg and spigot. Accordingly, the combination ofa variable spigot pressure and constant time interval will produce aninconstant volume of liquid delivered.

The principal object of the present invention, which is designed toovercome the disadvantages referred to, is to provide an improvedapparatus for intermittently dispensing rapidly successivevolumetrically predetermined quantities of foamable liquid, underpressure, wherein the quantity of liquid delivered is not sensitive tovariations in the spigot pressure due to frictionless delivered on thefirst pour of the series is substantially equal to the volume deliveredon each of the subsequentpours of the series, such being accomplished bythe provision of a flow pressure control valve in the circuit adjacentthe spigot end, which maintains the equivalent of flow pressure p, onthe spigot even though liq uid is not then flowing in the system andwhich isolates the spigot from the higher or keg pressure p Theinvention, both as to its organization and method of operation, togetherwith further objects and advantages thereof, will best be understood byreference to the following detailed specification, taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a schematic partly sectional view of a draft beer dispensingspigot according to the present invention illustrating the draft beercircuit, and details of the spigot.

FIG. 2 is a cross-sectional view of the flow pressure control valve.

Referring to the drawings, the draft beer circuit comprises generally akeg 1 l, carrying draft beer under initial static pressure p of theorder of pounds per square inch gauge, which is tapped by flow'line 12leading to the beer spigot generally designated 13. In order to maintainthe drive, supplemental air under pressure is supplied from a compressoror a cylinder 14, controlled by a pressure regulator 15, to the keg IIby the air flow line 16. v i

In the embodiment depicted in FIG. 1, a receiver 25 is positioned in thebeer flow line 12, adjacent to the spigot 13, the purposes of which isto minimize foaming of the liquid in the line and to dampen outirregularities in the dynamics of the circuit. A flow pressure controlvalve generally designated 26 is located in the flow line 12 adjacentand up-stream from the receiver 25, the purpose and function of whichwill hereafter be explained.

The spigot 13 is of standard design, of the push-pull manual type,lateral movement of the lever 17, comprising the spigot handle, causingthe valve (not illustrated) to open, as will be well understood by thosefamiliar with the art to which this invention relates.

The manually operated spigot 13 has been altered by the removal of thehandle from the lever 17, and the addition of the rotary solenoidgenerally designated 18 and the toggle switch 19 positioned on the topof the spigot. The rotary solenoid 18 includes a armature 20 and linkage21 operatively connected to the spigot lever 17, so that movement of therotary armature through 180 will be translated into lateral movement ofthe lever 17 from its vertical closed position to its fully openedposition as indicated by the broken line 22. The armature 20 is rigidlymounted on the spigot 13 by means of mounting bracket 23, secured byretainer nut 24.

The spigot solenoid 18 is energized from an electrical timing means,indicated schematically in FIG. I at 27,

which may conveniently be of the resistor-capacitor type. In this typeof time circuit, which is well known to those skilled in the art towhich this invention relates, an electrical charge builds up on one ormore capacitors which, in accordance with the characteristics of thecircuit, discharges after reaching a variably determinable level,causing a current flow which is amplitied and modified to operate thespigot solenoid 18. Control is included in the electrical timing means27 whereby the number of discharges, the length of each discharge andthe interval between discharges of the electrical timing means isdetermined, such being also common to and well-known in the art to whichthis invention relates.

The essence of the present invention, however, resides in the provisionof the flow pressure control valve 26 in the beer flow line 12, adjacentthe spigot 13. The valve 26 regulates the fluid flowing under the linepressure of line 12, and is controlled from the electrical timing means27, conveniently by the air assist end 28 of the valve 26, as indicatedin FIG. 1. Control air under pressure is admitted to the diaphragm typeair valve 29, controlled by the solenoid valves 30 and 30', which areenergized from the electrical timing means 27, so that operation of theswitch 19 to the on position to open the spigot valve 13 will alsosimultaneously open the flow pressure control valve 26, which latterwill remain open until switch 19 is operated to the of position,whereupon the flow pressure control valve 26 will close.

Functionally, the purpose of the flow pressure control valve 26 will beseen to isolate the receiver 25 and the spigot 13 from the higher staticp pressure of the keg 11, so that only the lower flowing pressure p,will prevail on the downstream side of the flow pressure control valve26. This will be appreciated when it is understood that under flowingconditions in the example referred to, the pressure p within the keg llof, say 40,

p.s.i.g., will drop to a flow pressure p, of 28 p.s.i.g. at the spigot13, due to line losses. Thus, when the spigot 13 and the flow pressurecontrol valve 26 simultaneously close, the portion of the liquid circuitbetween these points will be maintained at a static pressuresubstantially equivalent to the flow pressure p,i.e., approximately 28p.s.i.g. in the example given; upstream from the flow pressure conrolvalve 26, the higher static keg pressure p} of 40 p.s.i.g. will prevail.Thus, when the spigot is opened for a series of intermittent pours, thefirst pour and each subsequent pour will be made at substantially equalspigot pressures, rather than varying from static keg pressure p for theinitial pour, then dropping to the substantially lower flow pressure p,for each subsequent pour of the rapidly intermittent series. Suchundesirable variation in spigot pressure, when associated with equalperiods of spigot valve opening, will of course result in undesirablysignificant variations in the volume of liquid delivered at the spigotbetween the first pour of a rapidly intermittent series and eachsubsequent pour of such series.

In operation, the operator will introduce the glass to be filled at thespigot; the timer 27 is assumed to be energized froma suitable powersupply, and the operator will actuate the switch 19 in order to initiatethe automatic dispensing cycle. The reduced flow pressure p,

rest. Upon the firing of the timer 27, a pulse will energize the spigotsolenoid 18, causing it to rotate and thereby opening the spigot valve17 through the linkage 21. Simultaneously with the opening of the spigotvalve 17, the flow pressure control valve 26 is opened through theenergizing of the solenoidoperated air relays 30 and 30' which admit airto the one side of the diaphragm valve 29, thereby opening the receiver25 to flow pressure p, in the flow line 12. As beer in the circuit movesin response to the keg pressure p within the supply keg 11, a frictionhead is developed between the keg 11 and the spigot valve 13, causing adrop in pressure to the spigot pressure, which will be essentially theflow pressure p,. Subsequent firing of the timer 27 in the cycle willcause a pulse to reenergize the spigot solenoid 18 in the reversedirection thereby closing the spigot valve 17, and simultaneouslyclosing the flow pressure control valve 26. The portion of the circuitdownstream from the flow pressure control valve 26 will remain atsubstantially flow pressure p,, while the pressure within the circuitupstream from the control valve 26 will stabilize at the higher kegpressure p The flow of beer is thus momentarily interrupted, permittingthe operator to remove the filled glass and to substitute an emptyglass.

Upon the firing of the timer 17 in the next following sequence in thetimer cycle, the spigot solenoid 18 is re-energized in the reversedirection, causing movement into the open position of the spigot 17; theflow pressure control valve 26 is simultaneously opened to the flow line12; the beer in the portion of the circuit downstream from the flowpressure control valve 26 will flow under flow pressure p,, which hasprevailed in that portion of the circuit, and not the higher kegpressure p In similar fashion, the timer will deliver accuratelycontrolled quantities of beer at the spigot as long as the lever 17 ismaintained'in its open position; when lever 17 is moved to its closedposition following completion of a pour, the cycle is terminated, andthe circuit will resume equilibrium under the two pressures p, and pprevailing on opposite sides of the flow control valve 26.

The advantages resulting from the introduction of the flow pressurecontrol valve in the circuit, positioned adjacent the receiver 25 andthe spigot 13, insulating that portion of the circuit downstream fromthe flow pressure control valve from the upstream portion, except duringconditions of flow, will be appreciated to be the equilization of volumeof all pours from the system in a relatively simple and inexpensivemanner, thereby solving a problem that heretofore has restricted theintroduction and use of automated beer dispensing apparatus.

Since various modifications can be made in the invention, as hereinabove described, and in many apparently widely different embodiments ofsame made within the spirit and scope of the claims without departingfrom such spirit and scope, it is intended that all matters in theaccompanying specifications shall be interpreted as illstrative only andnot in a limiting sense.

What I claim as my invention is:

1. Apparatus for automatic controlled dispensing of successive pours ofdraft beer, subject to foaming as it is dispensed comprising, incombination;

a source of draft beer under pressure,

a flow line connecting with said source a spigot valve connected withsaid flow line,

a flow pressure control valve positioned in said flow line adjacent saidspigot valve,

power means for operating said flow pressure control valve and saidspigot valve,

timer means operatively connected with said power means, adapted tooperate successively intermittently said spigot valve and said flowpressure con trol valve substantially simultaneously, and

switch means operatively connected with said timer means whereby theoperator may initiate and terminate the cycle of said successive pours.

2. Apparatus for automatic controlled dispensing of successive pours ofdraft beer according to claim 1 in diate said spigot valve and said flowpressure control

1. Apparatus for automatic controlled dispensing of successive pours ofdraft beer, subject to foaming as it is dispensed comprising, incombination; a source of draft beer under pressure, a flow lineconnecting with said source a spigot valve connected with said flowline, a flow pressure control valve positioned in said flow lineadjacent said spigot valve, power means for operating said flow pressurecontrol valve and said spigot valve, timer means operatively connectedwith said power means, adapted to operate successively intermittentlysaid spigot valve and said flow pressure control valve substantiallysimultaneously, and switch means operatively connected with said timermeans whereby the operator may initiate and terminate the cycle of saidsuccessive pours.
 2. Apparatus for automatic controlled dispensing ofsuccessive pours of draft beer according to claim 1 in which said timermeans includes control means for varying the time period during whichsaid spigot valve and said flow pressure control valve remain open andremain closed, respectively.
 3. Apparatus for automatic controlleddispensing of successive pours of draft beer according to claim 1 inwhich a receiver is positioned in said flow line intermediate saidspigot valve and said flow pressure control valve.
 4. Apparatus forautomatic controlled dispensing of successive pours of draft beeraccording to claim 2 in which a receiver is positioned in said flow lineintermediate said spigot valve and said flow pressure control valve.